Improvement in the manufacture of coal-gas



PATENT OFFICE.

DARIUS DAVISON, OF NEW YORK, N. Y.

IMPROVEMENT IN THE MANUFACTURE OF COAL-GAS.

Specification forming part of Letters Patent No. 120,151, dated October24, 1871; antedated October 6, 1871.

To all whom t may concern:

Be it known that I, DAEIUs DAvTsoN, of the city, county, and State ofNew York, have invented a new and useful Improvement in the Manufactureof Goal-Gas, of which the following is a full, clear, andexact-description, reference being had to the accompanying drawingforming part of this specification, and in which- Figure 1 represents alongitudinal sectional elevation of an ordinary gas-retort charged withcoal in accordance with the invention; Fig. 2, a similar View, showingthe retort in the act of being charged 5 Fig. 3, a plan of an implementused to charge the retort; and Fig. 4, a view in perspective of a slideused in combination with said implement when charging' the retort, asillustrated in Fig. 2. l

Similar' letters of reference indicate corresponding parts.

My invention consists in a novel introduction and distribution of thecharge in the retort and manner of working the same, for the productionof illuminatinggas bythe destructive distillation of coal, thesamecausing a more equable exposure of the gas and vapor to the heatedsurfaces of the retort, whereby an increased quantity and improvedquality of gas is produced; also, considerable economy eifected in theproduction of it. To this end the usual whole charge is divided into twoequal parts and each of such divided portions is deposited at the backend of the retort at certain successive intervals. The invention alsoincludes a peculiarly-constructed charging implement, made up of asliding scraper and hod for placing the charge or partial charge in therear of the retort; also, a slide for facilitating the passage of a newcharge or partial charge over and in the rear of a partly distilled one.

To clearly explain my improvement, it will be necessary, by way ofpointing out the defects which it is the object of my invention toavoid, to refer brieiiy to the process heretofore adopted of chargingand working' the charge in a retort. Supposing the whole charge to betwo hundred pounds of coal, which is about the usual amount, and willhere, for the purpose of explaining the invention, be assumed throughoutthis description, the same is ordinarily put into the retort at one andthe same time and spread over the entire bottom of the retort throughoutits length, where it is allowed to remain for about four hours,

till the gas is exhausted from the charge. This mode of operation causesa large volume of vapor to be disengaged when the charge is introduced,and a gradually-diminishing volume afterward, till the operation iscompleted, so that the How of gas fromthe retort is unequal throughoutthe distillation of the charge, the gas and vapor passing rapidly fromthe retort at rst and gradually diminishing in velocity and volume tothe end. This causes an unequal action on the gas and vapor in contactwith the heated surfaces of the retort. Much of the vapor distilled fromthe coal at and near the mouth of the retort passes from the retortunconverted into gas, and is lost under the ordinary process ofproducing gas. The gas produced, too, from the coal during the latterpart of the process of distilling it,\under the method heretoforepracticed, passes so slowly from the retort by reason of its reducedvolume that part of the gas is burned in the retort and converted intofixed carbon or lampblack, thus further reducing the volume andilluminating quality of the gas produced.

To obviate these defects, instead of placing the entire charge at onefeed, as described, I divide the amount of such one charge into twoequal parts and introduce each part to the retort at about equalintervals of time. For instance, if the charge of two hundred pounds isdivided into two equal parts, half thereof would be charred in the backend of the retort and allowed to distil about two hours, more or less,after which the retort is opened and such partially-distilled halfcharge hauled forward on the bottom of the retort, and the remaininghalf charge introduced over it to the rear of the retort. This method ofcharging is represented in Figs. 1 and 2 of the drawing. The two halfcharges are then allowed to distil for about two hours, making fourhours in all, or thereabout, for the iirst half charge, from whichlatter the gas and vapor being all distilled, the same is then drawnfrom the retort and the remaining half of the charge at the back endhauled forward and a fresh half charge introduced over it in the rear,and a repetition of the process just described continued. By dividingand distributing the charge, as speciiied, then the reduced quantity ofesh coal introduced into the retort at a time yields a less voluminousamount of vapor, and consequently said vapor passes more slowly out ofthe retort and prolongs its exposure to the hot surfaces of the latter.Likewise, the rich gas and vapor from the fresh coal has to pass overthe heated partly-distilled pile of coal in front of it, and isconsequently combined with the poorer gas being eliminated from thepartly-distilled portion of coal drawn toward the mouth of the retort.Furthermore, dividing the entire charge and introducingl the dividedportions at successive intervals, as described, effects a nearly-uniformdistillation in volume of vapor and gas, and consequently a more nearlyuniform flow of Ygas in volume from the retort continually, 7thusobtaining ta more nearly uniform action of the heat, both as regardstime and space, and a thorough mixing of all the products ofdistillation, together with a very thorough conversion of all the vaporsfrom the coal into permanent rich illuminating-gas. To facilitate theplacing` of the partial charge at the extreme back end of the retort, acharger, such as illustrated in Figs. 2 and 3, may be used, the sameconsisting of a sliding scraper, I), and a hod, c, within which latterthe scraper is arranged, said hod having a rear extension provided witha handle, d, for pushing in or drawing out the whole ilnplement. Thescraper b is operated by a rod or handle, e, running sufficientlybackward to allow of the scrapers operation from a position in front ofthe retort after the implement has been introduced its full lengththerein. To discharge the coal the scraper b is held stationary whilethe hod c is drawn outward, which deposits the coal as required, or saidscraper may be pushed inward simultaneously with the drawing outward ofthe hod. To deposit a charge over a previous charge lying in the retort,as shown in Fig. 2, a stationary incline or slide, j', of a length tosuit, and provided with a stop, g, at its back that strikes against thefront of the retort, to gauge the position of the slide in the latter,is used. This slide, which is inserted at each opening of the retort andwithdrawn at each closing thereof, is projected within the retort tillits front end rests on or overhangs the pile or partial charge drawnfrom its position in rear of the retort to make room for a fresh charge.Said slide maybe made arched in its transverse section, to guide andsteady the charger along and over it.

The improved implements for charging retorts and the process ofmanufacturing coal-gas herein described are designed to be applied toand used in connection with retorts at present in use in gas-works, asWell as in new retorts, without V'any' 'material change in the presentYplan of con-V Y structing retorts and without any change in the variousapparatus and processes for manufacturing illuminating-gas after 'thesame passes from the retort or retorts.

What is here claimed, and desired to be secured by Letters Patent, is

l. The process herein described of manufacturing coal-gas by dividingthe usual whole charge into two equal parts, or thereabout, anddepositing each fresh supplyof a divided charge in rear of the retortand successively distributing a series of such partial whole chargeswithin the retort at intervals in a progressive manner from the reartoward the mouth of the retort, essentially as herein set forth.

2. The slide c, constructed for operation within the retort, to pass theone charge or partial charge over and in rear of another, substantiallyas speciied.

3. The charger, composed of a sliding scraper, b, and hod c, constructedand arranged for operation in relation with each other and the retort,essentially as shown and described.

DARIUS DAVISON.

lt. E. RABEAU. (66)

